In the prior art, it has been known for a long time that by forming a peelable curable coating on the surface of various substrate materials such as paper, synthetic resin film, synthetic fiber cloth, etc., it is possible to obtain a material which displays a release property with respect to pressure-sensitive adhesive or other adhesive substances. Usually, a curable organopolysiloxane composition is used as the material for forming the release coating. Examples include curable organopolysiloxane compositions made of vinyl radical-containing organopolysiloxane, organohydrodienepolysiloxane having silicon-bonded hydrogen atoms, organic compound having perfluoroalkyl radicals, and platinum series compound (see Japanese Kokoku Patent Application No. Sho 63-48901) and curable organopolysiloxane compositions made of diorganopolysiloxane containing fluoroalkyl radicals and vinyl radicals, organohydrogenpolysiloxane, and platinum series compound (Japanese Kokai Patent Application No. Sho 63-320). However, for these conventional types of curable organopolysiloxane compositions, the curing rate is low, and the release character is poor.